<template>
  <div class="cbox">
     <h3>{{fromParentMsg}}</h3>
     <h3>{{cmsg}}</h3>
     <button @click="sendMsgToParent">send</button>
  </div>
</template>

<script lang='ts'>
import {ref,reactive} from 'vue'
export default{
 props:['fromParentMsg'],
 data(){
    return{
        cmsg:20
    }
 },
 methods: {
    sendMsgToParent(){
        this.$emit('make',this.cmsg)
    }
 },
}
</script>

<style lang='scss' scoped>
.cbox{
    width: 200px;
    height: 100px;
    background-color: springgreen;
}
</style>